In those days, the road was so narrow it forced a single-file
march with heavilyladen mules. Today, the Route above Grasse is
still a long and very winding singlecarriageway, as the ground
rises rapidly, with the Col de Pilon at 786 metres above sea level
and the Col de Valferrière at 1,169 metres. Back in 1815 these
freezing tracks had to be traversed with mules, several of which
slipped on the treacherous mountain paths and fell to their deaths
hundreds of feet below.